Regulation and protection devices provide either alternative ratings through the selection of tap changer positions, or protection of the electrical equipment from network disturbances. In this field Weidmann offers tap changers, circuit breakers, arresters and fuses as well as positive pressure systems.
Arresters and fuses offer single use protection for electrical equipment. The arrester or fuse opens breaking the electrical circuit and must be replaced after the disturbance is cleared.
Tap changers provide the operational flexibility by permitting several output ratings. They are generally segregated into on-load and no-load applications. On-load tap changers are a transformer specific engineered application and are primarily used with the larger power transformers as a means of adjusting to load demand. Through the use of optional accessories, load tap changers can provide automatic tap changing functions. No-Load tap changers are more standardized and are used in small power and distribution transformers. Weidmann can provide a number of linear and rotary designed load and no-load tap changers.
The Buchholz relay is an important protection and monitoring device for insulating liquid filled-transformers with conservators and choke coils. It also allows separate monitoring of oil-filled bushings or cable terminal boxes.